\Tri"lo*bite\ (tr[imac]"l[-o]*b[imac]t), n. [Cf. F.
trilobite. See {Trilobate}.] (Paleon.)
Any one of numerous species of extinct arthropods belonging
to the order Trilobita. Trilobites were very common in the
Silurian and Devonian periods, but became extinct at the
close of the Paleozoic. So named from the three lobes usually
seen on each segment.